Abstracts

A multi-center feasibility investigation assessed safety and possible efficacy of the cranially based implantable, programmable Responsive Neurostimulator (RNS[trade]) system., Subjects were 18-65 years with intractable partial-onset seizures and localized epileptogenic onset region(s). Subjects with [underline][gt][/underline]12 simple partial (SP) sensory or motor seizures, complex partial seizures (CPS) or generalized tonic-clonic (GTC) seizures over an 84-day baseline period qualified for implant. The RNS was connected to up to 2 leads (subdural and/or depth), which were targeted to the seizure focus. Adverse events (AEs) were monitored throughout the trial. Efficacy was assessed during two time periods, the 84-day period beginning 28 days post-implant (primary) and the most recent 84 days for which a subject could have received therapy (secondary)., During the primary evaluation period, the responder rate ([underline][gt][/underline]50% reduction in seizures) in 50 subjects (excluding 1 subject with no disabling seizures at baseline and 14 subjects blinded off) was 32% for CPS (n=44), 63% for GTC (n=16), and 26% (n=50) for total disabling seizures (TDS) (SP motor, CPS and GTC). The median percentage reduction in seizure frequency was: CPS 27%, GTC 59% and TDS 29%; seizure reduction was significant for CPS (p[lt]0.05) and TDS (p[lt]0.001) (Wilcoxon signed-rank test).
For the secondary evaluation period, as of 4/28/06, the responder rate for 62 subjects (excluding 1 subject with no disabling seizures at baseline and 2 subjects previously blinded off with fewer than 84-days of therapy on) was 40% for CPS (n=52), 55% for GTC (n=22), and 41% for TDS (n=61). The median percentage reduction was: CPS 34%, GTC 66% and TDS 35%, and seizure reduction was significant for CPS (p[lt]0.05), GTC (p[lt]0.005), and TDS (p[lt]0.001).
In 65 implanted subjects (including 17 device replacements) representing 65 patient years, there were no serious unanticipated device-related AEs, and responsive neurostimulation was well tolerated., An investigation of the RNS[trade] system demonstrated safety and a sustained reduction in CPS, GTC and TDS events. Preliminary results indicated that the RNS[trade] system may provide a safe and effective treatment for adults with intractable partial-onset epilepsy., (Supported by NeuroPace, Inc.)